China Nonferrous Metallurgy

Rare metals support the economic development and advanced high-tech industries in various countries. China has a large reserve of rare metals and a high grade of raw ore, but its distribution is sparse, the amount of available per capita is small and the extraction rate is relatively low. The consumption of rich mineral resources cannot fully meet the needs of industrial production demands. Therefore, extracting or recovering rare metals from low-grade ore or waste has become a current research hotspot. The accumulation of solid waste seriously affects the acid-base balance of groundwater and topsoil, causes heavy metal pollution and destroys the original stable structure of ecosystem. Research has shown that a large amount of rare metal elements are enriched in solid waste, and the value-added of solid waste can be greatly increased by bioleaching technology. In this paper, the yield, physical and chemical properties, bioleaching mechanism, classification and process of several common solid wastes are introduced, and the research progress of common solid waste bioleaching technologies are summarized. The results show that the current solid waste bioleaching technology still faces many problems, such as low intelligent level, low short-term income, long cycle, and complex process link. There are difficulties and breakthroughs in the selection of new leaching strains, adaptability of microorganisms to solid waste, and specific extraction of single elements. A series of suggestions are put forward, such as closing to new quality productivity, developing intelligent bioleaching technology and optimizing process structure. The comprehensive utilization of solid waste is still in the developing stage. The research and development of resource-saving and environmentally friendly biological leaching technologies is of great significance for the efficient utilization of rare metal resources.